scholarly journals Restoring Shank3 in a rostral sensorimotor brainstem nucleus rescues reduced light-evoked behaviors in shank3ab-/- zebrafish.

2021 ◽  
Author(s):  
Robert Kozol ◽  
David James ◽  
Ivan Varela ◽  
Sureni Sumathipala ◽  
Stephan Züchner ◽  
...  
Keyword(s):  
Sensorimotor Integration ◽  
Brain Activity ◽  
Visual Stimuli ◽  
Brain Nuclei ◽  
Sensory Responsiveness ◽  
Brain Circuits ◽  
Brainstem Nucleus ◽  
Reduced Light ◽  
The Brain ◽  
Reduced Activity

Abstract People with Phelan-McDermid Syndrome, caused by mutations in the SHANK3 gene, commonly present with symptoms of sensory hyporeactivity. To investigate how shank3 mutations impact brain circuits and contribute to sensory hyporeactivity, we generated two shank3 zebrafish mutant models. These shank3 mutant models both exhibit hyporeactivity to visual stimuli. Using whole-brain activity mapping, we show that light receptive brain nuclei show normal levels of activity while sensorimotor integration and motor regions are less active in shank3-/- mutants. Specifically rescuing Shank3 in a sensorimotor nucleus of the rostral brainstem is sufficient to rescue shank3-/- mutant hyporeactivity. In summary, reduced sensory responsiveness in shank3-/- mutant is associated with reduced activity across the brain and can be rescued by restoring Shank3 function in the rostral brainstem.

Information-based Analysis of the Coupling between Dynamic Visual Stimuli, Eye Movements, and Brain Signals

2021 ◽  
pp. 2150048
Author(s):  
Hamidreza Namazi ◽  
Avinash Menon ◽  
Ondrej Krejcar
Keyword(s):  
Eye Movements ◽  
Moving Objects ◽  
Brain Activity ◽  
Visual Stimuli ◽  
Strongly Correlated ◽  
Eeg Signals ◽  
Vision Science ◽  
Brain Signals ◽  
Information Contents ◽  
The Brain

Our eyes are always in search of exploring our surrounding environment. The brain controls our eyes’ activities through the nervous system. Hence, analyzing the correlation between the activities of the eyes and brain is an important area of research in vision science. This paper evaluates the coupling between the reactions of the eyes and the brain in response to different moving visual stimuli. Since both eye movements and EEG signals (as the indicator of brain activity) contain information, we employed Shannon entropy to decode the coupling between them. Ten subjects looked at four moving objects (dynamic visual stimuli) with different information contents while we recorded their EEG signals and eye movements. The results demonstrated that the changes in the information contents of eye movements and EEG signals are strongly correlated ([Formula: see text]), which indicates a strong correlation between brain and eye activities. This analysis could be extended to evaluate the correlation between the activities of other organs versus the brain.

Brain-Computer Interfaces and Visual Activity

2013 ◽  
pp. 1549-1570
Author(s):  
Carmen Vidaurre ◽  
Andrea Kübler ◽  
Michael Tangermann ◽  
Klaus-Robert Müller ◽  
José del R. Millán
Keyword(s):  
Video Game ◽  
Brain Activity ◽  
Visual Stimuli ◽  
Robot Arm ◽  
Virtual Keyboard ◽  
Computer Interfaces ◽  
Brain Signals ◽  
Brain States ◽  
Physically Disabled People ◽  
The Brain

There is growing interest in the use of brain signals for communication and operation of devices, in particular, for physically disabled people. Brain states can be detected and translated into actions such as selecting a letter from a virtual keyboard, playing a video game, or moving a robot arm. This chapter presents what is known about the effects of visual stimuli on brain activity and introduces means of monitoring brain activity. Possibilities of brain-controlled interfaces, either with the brain signals as the sole input or in combination with the measured point of gaze, are discussed.

Experimental models of spatial neglect

e-Neuroforum ◽  
2012 ◽  
Vol 18 (1) ◽  
Author(s):  
M. Wilke ◽  
P. Dechent ◽  
C. Schmidt-Samoa
Keyword(s):  
Nonhuman Primates ◽  
Brain Activity ◽  
Brain Regions ◽  
Experimental Models ◽  
Spatial Neglect ◽  
Distributed Network ◽  
Healthy Individuals ◽  
Detailed Understanding ◽  
Brain Circuits ◽  
The Brain

AbstractSpatial neglect is a debilitating neuropsy­chological disorder that is characterized by an impaired or lost ability to explore the space contralateral to the lesion and to re­act to stimuli presented on this side. Lesion sites that have been implicated in spatial ne­glect form a widely distributed network con­sisting of a number of cortical (i.e., frontopa­rietal) and subcortical (i.e., thalamic) areas that are activated during attention and vi­suomotor tasks in healthy individuals. While detailed understanding of the brain circuits and mechanisms involved in spatial neglect is a prerequisite for the development of ef­fective therapies, this has proven to be dif­ficult in human patients because of the size and variability of lesion sites. Therefore, ex­perimental models where predefined brain regions can be systematically inactivated are of great advantage. Neglect models have been developed in nonhuman primates in whom it is possible to pharmacologically in­activate small brain regions and in humans by means of noninvasive stimulation/inacti­vation methods such as transcranial magnet­ic stimulation. In this article, we discuss theo­ries about the mechanisms of spatial neglect such as the hemispheric imbalance model and the supporting experimental evidence, with an emphasis on imaging experiments that have explored the effects of lesions on dynamic brain activity.

scholarly journals Restoring Shank3 in the rostral brainstem of shank3ab−/− zebrafish autism models rescues sensory deficits

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Robert A. Kozol ◽  
David M. James ◽  
Ivan Varela ◽  
Sureni H. Sumathipala ◽  
Stephan Züchner ◽  
...  
Keyword(s):  
Sensory Processing ◽  
Sensorimotor Integration ◽  
Brain Regions ◽  
Wild Type ◽  
Sensory Stimuli ◽  
Sensory Deficits ◽  
Light Sensing ◽  
Sensory Responsiveness ◽  
Behavioral Adaptations ◽  
Reduced Activity

AbstractPeople with Phelan-McDermid Syndrome, caused by mutations in the SHANK3 gene, commonly exhibit reduced responses to sensory stimuli; yet the changes in brain-wide activity that link these symptoms to mutations in the shank3 gene remain unknown. Here we quantify movement in response to sudden darkness in larvae of two shank3 zebrafish mutant models and show that both models exhibit dampened responses to this stimulus. Using brain-wide activity mapping, we find that shank3−/− light-sensing brain regions show normal levels of activity while sensorimotor integration and motor regions are less active. Specifically restoring Shank3 function in a sensorimotor nucleus of the rostral brainstem enables the shank3−/− model to respond like wild-type. In sum, we find that reduced sensory responsiveness in shank3−/− models is associated with reduced activity in sensory processing brain regions and can be rescued by restoring Shank3 function in the rostral brainstem. These studies highlight the importance of Shank3 function in the rostral brainstem for integrating sensory inputs to generate behavioral adaptations to changing sensory stimuli.

scholarly journals Origins of the brain networks for advanced mathematics in expert mathematicians

2016 ◽  
Vol 113 (18) ◽  
pp. 4909-4917 ◽  
Author(s):  
Marie Amalric ◽  
Stanislas Dehaene
Keyword(s):  
Brain Activity ◽  
Basic Number ◽  
Advanced Mathematics ◽  
Language Competence ◽  
Academic Standing ◽  
Brain Circuits ◽  
Brain Circuit ◽  
High Level ◽  
The Brain ◽  
Mathematical Expertise

The origins of human abilities for mathematics are debated: Some theories suggest that they are founded upon evolutionarily ancient brain circuits for number and space and others that they are grounded in language competence. To evaluate what brain systems underlie higher mathematics, we scanned professional mathematicians and mathematically naive subjects of equal academic standing as they evaluated the truth of advanced mathematical and nonmathematical statements. In professional mathematicians only, mathematical statements, whether in algebra, analysis, topology or geometry, activated a reproducible set of bilateral frontal, Intraparietal, and ventrolateral temporal regions. Crucially, these activations spared areas related to language and to general-knowledge semantics. Rather, mathematical judgments were related to an amplification of brain activity at sites that are activated by numbers and formulas in nonmathematicians, with a corresponding reduction in nearby face responses. The evidence suggests that high-level mathematical expertise and basic number sense share common roots in a nonlinguistic brain circuit.

Brain-Computer Interfaces and Visual Activity

2012 ◽  
pp. 153-174
Author(s):  
Carmen Vidaurre ◽  
Andrea Kübler ◽  
Michael Tangermann ◽  
Klaus-Robert Müller ◽  
José del R. Millán
Keyword(s):  
Video Game ◽  
Brain Activity ◽  
Visual Stimuli ◽  
Robot Arm ◽  
Virtual Keyboard ◽  
Computer Interfaces ◽  
Brain Signals ◽  
Brain States ◽  
Physically Disabled People ◽  
The Brain

There is growing interest in the use of brain signals for communication and operation of devices – in particular, for physically disabled people. Brain states can be detected and translated into actions such as selecting a letter from a virtual keyboard, playing a video game, or moving a robot arm. This chapter presents what is known about the effects of visual stimuli on brain activity and introduces means of monitoring brain activity. Possibilities of brain-controlled interfaces, either with the brain signals as the sole input or in combination with the measured point of gaze, are discussed.

Evaluation of the Coupling between the Brain and Facial Muscles Reactions to Moving Visual Stimuli

2021 ◽  
pp. 2150042
Author(s):  
Mirra Soundirarajan ◽  
Ondrej Krejcar ◽  
Hamidreza Namazi
Keyword(s):  
Visual Stimulus ◽  
Hurst Exponent ◽  
Daily Life ◽  
Brain Activity ◽  
Pearson Correlation ◽  
Visual Stimuli ◽  
Physiological Signals ◽  
Eeg Signals ◽  
Facial Muscles ◽  
The Brain

Since the brain regulates our facial reactions, there should be a relationship between their activities. Moving (dynamic) visual stimuli are an important type of visual stimuli that we are dealing with in our daily life. Since EMG and EEG signals contain information, we evaluated the coupling of the reactions of facial muscles and brain to various moving visual stimuli by analysis of the embedded information in these signals. We benefited from Shannon entropy to quantify the information. The results showed that a decrement in the information of visual stimulus is mapped on a decrement of the information of EMG and EEG signals, and therefore, the activities of facial muscles and the brain are correlated (Pearson correlation [Formula: see text]). Besides, the analysis of the Hurst exponent of EEG signals demonstrated that increasing the information of EEG signals causes the increment in its memory. This method can also be used to evaluate the coupling among other organs’ activity and brain activity by analysis of related physiological signals.

Complexity Measures of Brain Electrophysiological Activity

2010 ◽  
Vol 24 (2) ◽  
pp. 131-135 ◽  
Author(s):  
Włodzimierz Klonowski ◽  
Pawel Stepien ◽  
Robert Stepien
Keyword(s):  
Brain Activity ◽  
Deterministic Chaos ◽  
Epileptic Seizures ◽  
Eeg Signal ◽  
Eeg Signals ◽  
Complexity Measures ◽  
Electrophysiological Activity ◽  
Signal Complexity ◽  
Physiological Sleep ◽  
The Brain

Over 20 years ago, Watt and Hameroff (1987 ) suggested that consciousness may be described as a manifestation of deterministic chaos in the brain/mind. To analyze EEG-signal complexity, we used Higuchi’s fractal dimension in time domain and symbolic analysis methods. Our results of analysis of EEG-signals under anesthesia, during physiological sleep, and during epileptic seizures lead to a conclusion similar to that of Watt and Hameroff: Brain activity, measured by complexity of the EEG-signal, diminishes (becomes less chaotic) when consciousness is being “switched off”. So, consciousness may be described as a manifestation of deterministic chaos in the brain/mind.

Relation Between Level of Prefrontal Activity and Subject's Performance

1999 ◽  
Vol 13 (2) ◽  
pp. 117-125 ◽  
Author(s):  
Laurence Casini ◽  
Françoise Macar ◽  
Marie-Hélène Giard
Keyword(s):  
Brain Activity ◽  
Sensory Information ◽  
Practice Phase ◽  
Trained Subjects ◽  
Anagram Task ◽  
Economic Information ◽  
Long Duration ◽  
Level Of Activity ◽  
The Brain ◽  
Processing Mechanism

Abstract The experiment reported here was aimed at determining whether the level of brain activity can be related to performance in trained subjects. Two tasks were compared: a temporal and a linguistic task. An array of four letters appeared on a screen. In the temporal task, subjects had to decide whether the letters remained on the screen for a short or a long duration as learned in a practice phase. In the linguistic task, they had to determine whether the four letters could form a word or not (anagram task). These tasks allowed us to compare the level of brain activity obtained in correct and incorrect responses. The current density measures recorded over prefrontal areas showed a relationship between the performance and the level of activity in the temporal task only. The level of activity obtained with correct responses was lower than that obtained with incorrect responses. This suggests that a good temporal performance could be the result of an efficacious, but economic, information-processing mechanism in the brain. In addition, the absence of this relation in the anagram task results in the question of whether this relation is specific to the processing of sensory information only.

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